Stateful NAT Failover
Problem
You want to use NAT in a high availability configuration, allowing a second router to take over NAT functionality if the first fails.
Solution
Stateful NAT allows you to combine NAT functionality with HSRP using two routers in a high availability configuration:
Router-A#configure terminal Enter configuration commands, one per line. End with CNTL/Z. Router-A(config)#access-list 11 permit any Router-A(config)#ip nat pool NATPOOL 172.17.100.100 172.17.100.150 netmask 255.255.255.0 Router-A(config)#ip nat inside source list 11 pool NATPOOL mapping-id 1 Router-A(config)#interface FastEthernet0/0 Router-A(config-if)#ip address 192.168.1.3 255.255.255.0 Router-A(config-if)#ip nat inside Router-A(config-if)#standby 1 ip 192.168.1.1 Router-A(config-if)#standby 1 preempt Router-A(config-if)#standby 1 name SNATGROUP Router-A(config-if)#exit Router-A(config)#interface Serial0/0 Router-A(config-if)#ip address 172.17.55.2 255.255.255.252 Router-A(config-if)#ip nat outside Router-A(config-if)#exit Router-A(config)#ip nat Stateful id 1 Router-A(config-ipnat-snat)#redundancy SNATGROUP Router(config-ipnat-snat-red)#mapping-id 1 Router(config-ipnat-snat-red)#exit Router-A(config)#end Router-A#
The second router's configuration is nearly identical:
Router-B#configure terminal Enter configuration commands, one per line. End with CNTL/Z. Router-B(config)#access-list 11 permit any Router-B(config)#ip nat pool NATPOOL 172.17.100.100 172.17.100.150 netmask 255.255.255.0 Router-B(config)#ip nat inside source list 11 pool NATPOOL mapping-id 1 Router-B(config)#interface FastEthernet0/0 Router-B(config-if)#ip address 192.168.1.2 255.255.255.0 Router-B(config-if)#ip nat inside Router-B(config-if)#standby 1 ip 192.168.1.1 Router-B(config-if)#standby 1 priority 90 Router-B(config-if)#standby 1 preempt Router-B(config-if)#standby 1 name SNATGROUP Router-B(config-if)#exit Router-B(config)#interface Serial0/0 Router-B(config-if)#ip address 172.17.55.6 255.255.255.252 Router-B(config-if)#ip nat outside Router-B(config-if)#exit Router-B(config)#ip nat Stateful id 1 Router-B(config-ipnat-snat)#redundancy SNATGROUP Router(config-ipnat-snat-red)#mapping-id 1 Router(config-ipnat-snat-red)#exit Router-B(config)#end Router-B#
Discussion
When you use NAT with a router failover protocol such as HSRP, the backup router must be able to take over NAT functionality as well as the IP address of the primary router. The problem is that this necessarily includes the entire dynamic NAT translation table. Simply running NAT and HSRP on a pair of routers is not sufficient because any existing NAT session information will be lost when the backup router takes over.
Stateful Network Address Translation (SNAT) solves this problem. The key command, which must be present on both routers is the ip nat Stateful command, which became available in IOS Version 12.2(13)T:
Router-A(config)#ip nat Stateful id 1 Router-A(config-ipnat-snat)#redundancy SNATGROUP Router(config-ipnat-snat-red)#mapping-id 1 Router(config-ipnat-snat-red)#exit
There are a couple of things to notice here. First, the keyword Stateful will appear in your configuration capitalized like this. When you enter the command, it is case insensitive, however it can be slightly confusing because one usually expects IOS configuration keywords to be all lowercase. We often take advantage of this fact by deliberately capitalizing user-defined strings like SNATGROUP in this example, making the distinction from keywords obvious.
Entering the ip nat Stateful command puts you into a new configuration mode that allows you to associate a particular SNAT mapping ID with an HSRP group name. You can give the HSRP group a name with the standby name command as follows:
Router-A(config)#interface FastEthernet0/0 Router-A(config-if)#ip address 192.168.1.3 255.255.255.0 Router-A(config-if)#ip nat inside Router-A(config-if)#standby 1 ip 192.168.1.1 Router-A(config-if)#standby 1 preempt Router-A(config-if)#standby 1 name SNATGROUP
For more information on HSRP, please refer to Chapter 22.
In this example we have used a simple dynamic NAT configuration by using a pool called NATPOOL:
Router-A(config)#access-list 11 permit any Router-A(config)#ip nat pool NATPOOL 172.17.100.100 172.17.100.150 netmask 255.255.255.0 Router-A(config)#ip nat inside source list 11 pool NATPOOL mapping-id 1
We could have just as easily used other NAT configuration methods such as static NAT, or PAT address overloading, as described elsewhere in this chapter.
With this configuration, one of the routers will take the virtual IP address, 192.168.1.1, acting as the default gateway for the interior network. The second router will operate in a passive backup mode, waiting to take over this virtual IP address in case the first router fails. The first router will maintain the NAT table for all connections. This means that you have to be very careful to ensure that inbound traffic uses the same path as outbound traffic, or the NAT table may not be able to rewrite the inside global IP address to the correct inside local address.
When the primary router fails, HSRP allows the backup router to transparently take over the virtual IP address. At the same time, SNAT ensures that the NAT translation table is also up to date, allowing the backup router to take over all NAT functions.
You can also use SNAT to create a dual redundancy active/active configuration in which both routers are passing HSRP and NAT traffic. We discuss the HSRP side of this technique in more detail in Chapter 22. The key is to create two HSRP groups, each representing a different virtual IP address. We then assign different priorities to each group so that during normal operation, the first router is active for the first virtual IP address and the second is active for the other address. However, in case of a failure of either router, the other one can take over functionality for both:
Router-A#configure terminal Enter configuration commands, one per line. End with CNTL/Z. Router-A(config)#interface FastEthernet0/0 Router-A(config-if)#ip address 192.168.1.3 255.255.255.0 Router-A(config-if)#ip nat inside Router-A(config-if)#standby 1 ip 192.168.1.1 Router-A(config-if)#standby 1 preempt Router-A(config-if)#standby 1 name SNAT1 Router-A(config-if)#standby 2 ip 192.168.1.2 Router-A(config-if)#standby 2 priority 90 Router-A(config-if)#standby 2 preempt Router-A(config-if)#standby 2 name SNAT2 Router-A(config-if)#exit Router-A(config)#interface Serial0/0 Router-A(config-if)#ip address 172.17.55.2 255.255.255.252 Router-A(config-if)#ip nat outside Router-A(config-if)#exit Router-A(config)#ip nat Stateful id 1 Router-A(config-ipnat-snat)#redundancy SNAT1 Router(config-ipnat-snat-red)#mapping-id 1 Router(config-ipnat-snat-red)#redundancy SNAT2 Router(config-ipnat-snat-red)#mapping-id 2 Router(config-ipnat-snat-red)#exit Router-A(config)#access-list 11 permit any Router-A(config)#access-list 12 permit any Router-A(config)#ip nat pool NATPOOL1 172.17.100.100 172.17.100.150 netmask 255.255.255.0 Router-A(config)#ip nat inside source list 11 pool NATPOOL mapping-id 1 Router-A(config)#ip nat pool NATPOOL2 172.17.100.151 172.17.100.200 netmask 255.255.255.0 Router-A(config)#ip nat inside source list 12 pool NATPOOL mapping-id 2 Router-A(config)#end Router-A#
And the second router's configuration is similar:
Router-B#configure terminal Enter configuration commands, one per line. End with CNTL/Z. Router-B(config)#interface FastEthernet0/0 Router-B(config-if)#ip address 192.168.1.4 255.255.255.0 Router-B(config-if)#ip nat inside Router-B(config-if)#standby 1 ip 192.168.1.1 Router-B(config-if)#standby 1 preempt Router-B(config-if)#standby 1 name SNAT1 Router-B(config-if)#standby 1 priority 90 Router-B(config-if)#standby 2 ip 192.168.1.2 Router-B(config-if)#standby 2 preempt Router-B(config-if)#standby 2 name SNAT2 Router-B(config-if)#exit Router-B(config)#interface Serial0/0 Router-B(config-if)#ip address 172.17.55.6 255.255.255.252 Router-B(config-if)#ip nat outside Router-B(config-if)#exit Router-B(config)#ip nat Stateful id 1 Router-B(config-ipnat-snat)#redundancy SNAT1 Router(config-ipnat-snat-red)#mapping-id 1 Router(config-ipnat-snat-red)#redundancy SNAT2 Router(config-ipnat-snat-red)#mapping-id 1 Router(config-ipnat-snat-red)#exit Router-B(config)#access-list 11 permit any Router-B(config)#ip nat pool NATPOOL 172.17.100.100 172.17.100.150 netmask 255.255.255.0 Router-B(config)#ip nat inside source list 11 pool NATPOOL mapping-id 1 Router-B(config)#end Router-B#
Here we have mapped both HSRP groups to the same NAT mapping-id on both routers. Now they can freely allocate addresses from the same pool, and update one another in case either fails. Note that HSRP is the only high-availability protocol that works with SNAT. Other protocols such as VRRP and GLBP are not currently supported.
See Also
Chapter 22
Router Configuration and File Management
- Configuring the Router via TFTP
- Saving Router Configuration to Server
- Booting the Router Using a Remote Configuration File
- Storing Configuration Files Larger Than NVRAM
- Clearing the Startup Configuration
- Loading a New IOS Image
- Booting a Different IOS Image
- Booting over the Network
- Copying an IOS Image to a Server
- Copying an IOS Image Through the Console
- Deleting Files from Flash
- Partitioning Flash
- Using the Router as a TFTP Server
- Using FTP from the Router
- Generating Large Numbers of Router Configurations
- Changing the Configurations of Many Routers at Once
- Extracting Hardware Inventory Information
- Backing Up Router Configurations
- Warm Reload
- Warm Upgrade
- Configuration Archiving
- Locking Configuration Access
Router Management
- Creating Command Aliases
- Managing the Routers ARP Cache
- Tuning Router Buffers
- Auto Tuning Buffers
- Using the Cisco Discovery Protocol
- Disabling the Cisco Discovery Protocol
- Using the Small Servers
- Enabling HTTP Access to a Router
- Enabling Secure HTTP (HTTPS) Access to a Router
- Using Static Hostname Tables
- Enabling Domain Name Services
- Disabling Domain Name Lookups
- Specifying a Router Reload Time
- Scheduling of Router Commands
- Displaying Historical CPU Values
- Creating Exception Dump Files
- Generating a Report of Interface Information
- Generating a Report of Routing Table Information
- Generating a Report of ARP Table Information
- Generating a Server Host Table File
User Access and Privilege Levels
- Setting Up User IDs
- Encrypting Passwords
- Using Better Password-Encryption Techniques
- Removing Passwords from a Router Configuration File
- Deciphering Ciscos Weak Password Encryption
- Displaying Active Users
- Sending Messages to Other Users
- Changing the Number of VTYs
- Changing VTY Timeouts
- Restricting VTY Access by Protocol
- Enabling Absolute Timeouts on VTY Lines
- Implementing Banners
- Disabling Banners on a Port
- Disabling Router Lines
- Reserving a VTY Port for Administrative Access
- Restricting Inbound Telnet Access
- Logging Telnet Access
- Setting the Source Address for Telnet
- Automating the Login Sequence
- Using SSH for Secure Access
- Changing Privilege Level of IOS Commands
- Defining Per User Privileges
- Defining Per Port Privileges
TACACS+
- Authenticating Login IDs from a Central System
- Restricting Command Access
- Losing Access to the TACACS+ Server
- Disabling TACACS+ Authentication on a Particular Line
- Capturing User Keystrokes
- Logging System Events
- Setting the IP Source Address for TACACS+ Messages
- Sample Server Configuration Files
IP Routing
- Finding an IP Route
- Finding Types of IP Routes
- Converting Different Mask Formats
- Using Static Routing
- Floating Static Routes
- Using Policy-Based Routing to Route Based on Source Address
- Using Policy-Based Routing to Route Based on Application Type
- Examining Policy-Based Routing
- Changing Administrative Distances
- Routing Over Multiple Paths with Equal Costs
- Static Routes That Track Interfaces or Other Routes
- Keeping Statistics on Routing Table Changes
RIP
- Configuring RIP Version 1
- Filtering Routes with RIP
- Redistributing Static Routes into RIP
- Redistributing Routes Using Route Maps
- Creating a Default Route in RIP
- Disabling RIP on an Interface
- Default Passive Interface
- Unicast Updates for RIP
- Applying Offsets to Routes
- Adjusting Timers
- Configuring Interpacket Delay
- Enabling Nonperiodic Updates
- Increasing the RIP Input Queue
- Configuring RIP Version 2
- Enabling RIP Authentication
- RIP Route Summarization
- Route Tagging
EIGRP
- Configuring EIGRP
- Filtering Routes with EIGRP
- Redistributing Routes into EIGRP
- Redistributing Routes into EIGRP Using Route Maps
- Disabling EIGRP on an Interface
- Adjusting EIGRP Metrics
- Adjusting Timers
- Enabling EIGRP Authentication
- EIGRP Route Summarization
- Logging EIGRP Neighbor State Changes
- Limiting EIGRPs Bandwidth Utilization
- EIGRP Stub Routing
- Route Tagging
- Viewing EIGRP Status
OSPF
- Configuring OSPF
- Filtering Routes in OSPF
- Adjusting OSPF Costs
- Creating a Default Route in OSPF
- Redistributing Static Routes into OSPF
- Redistributing External Routes into OSPF
- Manipulating DR Selection
- Setting the OSPF RID
- Enabling OSPF Authentication
- Selecting the Appropriate Area Types
- Using OSPF on Dial Interfaces
- Summarizing Routes in OSPF
- Disabling OSPF on Certain Interfaces
- Changing the Network Type on an Interface
- OSPF Route Tagging
- Logging OSPF Adjacency Changes
- Adjusting OSPF Timers
- Reducing OSPF Traffic in Stable Networks
- OSPF Virtual Links
- Viewing OSPF Status with Domain Names
- Debugging OSPF
BGP
- Configuring BGP
- Using eBGP Multihop
- Adjusting the Next-Hop Attribute
- Connecting to Two ISPs
- Connecting to Two ISPs with Redundant Routers
- Restricting Networks Advertised to a BGP Peer
- Adjusting Local Preference Values
- Load-Balancing
- Removing Private ASNs from the AS Path
- Filtering BGP Routes Based on AS Paths
- Reducing the Size of the Received Routing Table
- Summarizing Outbound Routing Information
- Prepending ASNs to the AS Path
- Redistributing Routes with BGP
- Using Peer Groups
- Authenticating BGP Peers
- Using BGP Communities
- Using BGP Route Reflectors
- Putting It All Together
Frame Relay
- Setting Up Frame Relay with Point-to-Point Subinterfaces
- Adjusting LMI Options
- Setting Up Frame Relay with Map Statements
- Using Multipoint Subinterfaces
- Configuring Frame Relay SVCs
- Simulating a Frame Relay Cloud
- Compressing Frame Relay Data on a Subinterface
- Compressing Frame Relay Data with Maps
- PPP over Frame Relay
- Viewing Frame Relay Status Information
Handling Queuing and Congestion
- Fast Switching and CEF
- Setting the DSCP or TOS Field
- Using Priority Queuing
- Using Custom Queuing
- Using Custom Queues with Priority Queues
- Using Weighted Fair Queuing
- Using Class-Based Weighted Fair Queuing
- Using NBAR Classification
- Controlling Congestion with WRED
- Using RSVP
- Manual RSVP Reservations
- Aggregating RSVP Reservations
- Using Generic Traffic Shaping
- Using Frame-Relay Traffic Shaping
- Using Committed Access Rate
- Implementing Standards-Based Per-Hop Behavior
- AutoQoS
- Viewing Queue Parameters
Tunnels and VPNs
- Creating a Tunnel
- Tunneling Foreign Protocols in IP
- Tunneling with Dynamic Routing Protocols
- Viewing Tunnel Status
- Creating an Encrypted Router-to-Router VPN in a GRE Tunnel
- Creating an Encrypted VPN Between the LAN Interfaces of Two Routers
- Generating RSA Keys
- Creating a Router-to-Router VPN with RSA Keys
- Creating a VPN Between a Workstation and a Router
- Creating an SSL VPN
- Checking IPSec Protocol Status
Dial Backup
- Automating Dial Backup
- Using Dialer Interfaces
- Using an Async Modem on the AUX Port
- Using Backup Interfaces
- Using Dialer Watch
- Using Virtual Templates
- Ensuring Proper Disconnection
- View Dial Backup Status
- Debugging Dial Backup
NTP and Time
- Time-Stamping Router Logs
- Setting the Time
- Setting the Time Zone
- Adjusting for Daylight Saving Time
- Synchronizing the Time on All Routers (NTP)
- Configuring NTP Redundancy
- Setting the Router As the NTP Master for the Network
- Changing NTP Synchronization Periods
- Using NTP to Send Periodic Broadcast Time Updates
- Using NTP to Send Periodic Multicast Time Updates
- Enabling and Disabling NTP Per Interface
- NTP Authentication
- Limiting the Number of Peers
- Restricting Peers
- Setting the Clock Period
- Checking the NTP Status
- Debugging NTP
- NTP Logging
- Extended Daylight Saving Time
- NTP Server Configuration
DLSw
- Simple Bridging
- Configuring DLSw
- Using DLSw to Bridge Between Ethernet and Token Ring
- Converting Ethernet and Token Ring MAC Addresses
- Configuring SDLC
- Configuring SDLC for Multidrop Connections
- Using STUN
- Using BSTUN
- Controlling DLSw Packet Fragmentation
- Tagging DLSw Packets for QoS
- Supporting SNA Priorities
- DLSw+ Redundancy and Fault Tolerance
- Viewing DLSw Status Information
- Viewing SDLC Status Information
- Debugging DSLw
Router Interfaces and Media
- Viewing Interface Status
- Configuring Serial Interfaces
- Using an Internal T1 CSU/DSU
- Using an Internal ISDN PRI Module
- Using an Internal 56 Kbps CSU/DSU
- Configuring an Async Serial Interface
- Configuring ATM Subinterfaces
- Setting Payload Scrambling on an ATM Circuit
- Classical IP Over ATM
- Configuring Ethernet Interface Features
- Configuring Token Ring Interface Features
- Connecting VLAN Trunks with ISL
- Connecting VLAN Trunks with 802.1Q
- LPD Printer Support
Simple Network Management Protocol
- Configuring SNMP
- Extracting Router Information via SNMP Tools
- Recording Important Router Information for SNMP Access
- Using SNMP to Extract Inventory Information from a List of Routers
- Using Access Lists to Protect SNMP Access
- Logging Unauthorized SNMP Attempts
- Limiting MIB Access
- Using SNMP to Modify a Routers Running Configuration
- Using SNMP to Copy a New IOS Image
- Using SNMP to Perform Mass Configuration Changes
- Preventing Unauthorized Configuration Modifications
- Making Interface Table Numbers Permanent
- Enabling SNMP Traps and Informs
- Sending Syslog Messages As SNMP Traps and Informs
- Setting SNMP Packet Size
- Setting SNMP Queue Size
- Setting SNMP Timeout Values
- Disabling Link Up/Down Traps per Interface
- Setting the IP Source Address for SNMP Traps
- Using RMON to Send Traps
- Enabling SNMPv3
- Strong SNMPv3 Encryption
- Using SAA
Logging
- Enabling Local Router Logging
- Setting the Log Size
- Clearing the Routers Log
- Sending Log Messages to Your Screen
- Using a Remote Log Server
- Enabling Syslog on a Unix Server
- Changing the Default Log Facility
- Restricting What Log Messages Are Sent to the Server
- Setting the IP Source Address for Syslog Messages
- Logging Router Syslog Messages in Different Files
- Maintaining Syslog Files on the Server
- Testing the Syslog Sever Configuration
- Preventing the Most Common Messages from Being Logged
- Rate-Limiting Syslog Traffic
- Enabling Error Log Counting
- XML-Formatted Log Messages
- Modifying Log Messages
Access-Lists
- Filtering by Source or Destination IP Address
- Adding a Comment to an ACL
- Filtering by Application
- Filtering Based on TCP Header Flags
- Restricting TCP Session Direction
- Filtering Multiport Applications
- Filtering Based on DSCP and TOS
- Logging When an Access-List Is Used
- Logging TCP Sessions
- Analyzing ACL Log Entries
- Using Named and Reflexive Access-Lists
- Dealing with Passive Mode FTP
- Using Time-Based Access-Lists
- Filtering Based on Noncontiguous Ports
- Advanced Access-List Editing
- Filtering IPv6
DHCP
- Using IP Helper Addresses for DHCP
- Limiting the Impact of IP Helper Addresses
- Using DHCP to Dynamically Configure Router IP Addresses
- Dynamically Allocating Client IP Addresses via DHCP
- Defining DHCP Configuration Options
- Defining DHCP Lease Periods
- Allocating Static IP Addresses with DHCP
- Configuring a DHCP Database Client
- Configuring Multiple DHCP Servers per Subnet
- DHCP Static Mapping
- DHCP-Secured IP Address Assignment
- Showing DHCP Status
- Debugging DHCP
NAT
- Configuring Basic NAT Functionality
- Allocating External Addresses Dynamically
- Allocating External Addresses Statically
- Translating Some Addresses Statically and Others Dynamically
- Using Route Maps to Refine Static Translation Rules
- Translating in Both Directions Simultaneously
- Rewriting the Network Prefix
- Using NAT for Server Load Distribution
- Stateful NAT Failover
- Adjusting NAT Timers
- Changing TCP Ports for FTP
- Checking NAT Status
- Debugging NAT
First Hop Redundancy Protocols
- Configuring Basic HSRP Functionality
- Using HSRP Preempt
- Making HSRP React to Problems on Other Interfaces
- Load-Balancing with HSRP
- Redirecting ICMP with HSRP
- Manipulating HSRP Timers
- Using HSRP on Token Ring
- HSRP SNMP Support
- Increasing HSRP Security
- Showing HSRP State Information
- Debugging HSRP
- HSRP Version 2
- VRRP
- Gateway Load-Balancing Protocol
IP Multicast
- Configuring Basic Multicast Functionality with PIM-DM
- Routing Multicast Traffic with PIM-SM and BSR
- Routing Multicast Traffic with PIM-SM and Auto-RP
- Filtering PIM Neighbors
- Configuring Routing for a Low-Frequency Multicast Application
- Multicast over Frame Relay or ATM WANs
- Configuring CGMP
- Using IGMP Version 3
- Static Multicast Routes and Group Memberships
- Routing Multicast Traffic with MOSPF
- Routing Multicast Traffic with DVMRP
- DVMRP Tunnels
- Configuring Bidirectional PIM
- Controlling Multicast Scope with TTL
- Controlling Multicast Scope with Administratively Scoped Addressing
- Exchanging Multicast Routing Information with MBGP
- Using MSDP to Discover External Sources
- Configuring Anycast RP
- Converting Broadcasts to Multicasts
- Showing Multicast Status
- Debugging Multicast Routing
IP Mobility
- Local Area Mobility
- Home Agent Configuration
- Foreign Agent Configuration
- Making a Router a Mobile Node
- Reverse-Tunnel Forwarding
- Using HSRP for Home Agent Redundancy
IPv6
- Automatically Generating IPv6 Addresses for an Interface
- Manually Configuring IPv6 Addresses on an Interface
- Configuring DHCP for IPv6
- Dynamic Routing with RIP
- Modifying the Default RIP Parameters
- IPv6 Route Filtering and Metric Manipulation in RIP
- Using OSPF for IPv6
- IPv6 Route Filtering and Metric Manipulation in OSPF
- Route Redistribution
- Dynamic Routing with MBGP
- Tunneling IPv6 Through an Existing IPv4 Network
- Translating Between IPv6 and IPv4
MPLS
- Configuring a Basic MPLS P Router
- Configuring a Basic MPLS PE Router
- Configuring Basic MPLS CE Routers
- Configuring MPLS over ATM
- PE-CE Communication via RIP
- PE-CE Communication via OSPF
- PE-CE Communication via EIGRP
- PE-CE Communication via BGP
- QoS over MPLS
- MPLS Traffic Engineering with Autoroute
- Multicast Over MPLS
- Your Service Provider Doesnt Do What You Want
Security
- Using AutoSecure
- Using Context-Based Access-Lists
- Transparent Cisco IOS Firewall
- Stopping Denial of Service Attacks
- Inspecting Applications on Different Port Numbers
- Intrusion Detection and Prevention
- Login Password Retry Lockout
- Authentication Proxy
Appendix 1. External Software Packages
Appendix 2. IP Precedence, TOS, and DSCP Classifications
- IP Precedence, TOS, and DSCP Classifications
- Queueing Algorithms
- Dropping Packets and Congestion Avoidance
Index
Cisco IOS Cookbook (Cookbooks (OReilly))
ISBN: 0596527225
EAN: 2147483647
EAN: 2147483647
Year: 2004
Pages: 505
Pages: 505
Authors: Kevin Dooley, Ian Brown
